The output of fecal bacteria as influenced by fasting and by high and low protein ingestion

Abstract

By means of a seven-day fast the daily excretion of fecal bacterial nitrogen by a 76-kilogram man (E) was reduced from 1.571 gram to 0.101 gram, whereas the actual weight of the excreted bacterial substance was reduced from 14.336 grams to 0.920 gram per day. The percentage of the fecal nitrogen which was present as bacterial nitrogen was decreased from 55.82 per cent. to 32.39 per cent. as a result of the fast. The percentage of dry bacteria in dry feces was slightly increased.

The output of bacterial nitrogen and the output of bacterial substance were approximately the same on a low protein diet as during fasting. With the ingestion of a high protein diet these values underwent an immediate pronounced increase.

The percentage of the fecal nitrogen which was composed of bacterial nitrogen was about the same in the periods of low and high protein ingestion.

There was no definite relationship between the excretion of fecal bacteria and that of urinary indican.

The ingestion of 5.23 grams of nitrogen after the fast was followed by an excretion of fecal bacteria which was only 1/14 as great as when four times that amount of nitrogen was ingested before the fast.